急性肺损伤时大鼠肺泡液体清除率的变化

The change of alveolar fluid clearance in acute lung injury rat

目的 制备盐酸吸入性急性肺损伤动物模型 ,测定其肺泡液体清除率。方法 32只大鼠随机分为 4组 ,对照组滴入pH为 7 4的 5 %等渗白蛋白溶液 ,酸吸入组分别滴注pH为 7 0、4 5、2 5的 5 %等渗白蛋白溶液 ,机械通气 1h后 ,测定其动脉血气、肺泡上皮屏障的通透性、肺泡液体清除率。结果 当滴注液pH值为 7 0时 ,其肺泡上皮对蛋白的通透性和对液体的清除率与对照组接近 ,动脉血氧分压无下降 (P >0 0 5 ) ;pH值为 4 5、2 5时 ,其肺泡上皮对蛋白的通透性和对液体清除率较对照组及pH 7 0组低 ,动脉血氧分压明显下降 (P <0 0 5 )。结论 肺泡上皮对酸损伤有一定的抵抗能力 ,高浓度盐酸溶液可损伤肺泡上皮和肺泡上皮屏障 ,使肺泡内液体不能及时清除 。

Objective To establish the animal model of lung injury caused by hydrochloric acid in rats, measure the alveolar fluid clearance(AFC) in different acidic condition. Methods 32 rats were randomly divided into 4 groups which were control group (pH=7.4) and HCl groups (pH=7.0, 4.5, 2.5). The animals were anesthetized and ventilated for 1 hour. Blood gas analysis was performed, then the permeability of lung epithelial barrier and AFC were measured. Results The permeability of lung epithelial barrier, PaO 2 and AFC of pH 7.0 group were similar to control group(P>0.05), but declined in pH 4.5 and 2.5 groups(P<0.05). Conclusions The alveolar epithelium and the alveolar epithelial barrier are resistant to the injurious effects of acid, but high concentration acid can induce damage.